Landing gear with shortening motion

Abstract

A landing gear for a vehicle includes a strut configured for reciprocating movement between a stowed position and a deployed position. A shock absorber has a first element slidingly disposed within the strut and a second element slidingly coupled to the first element. A trailing arm is rotatably coupled to the second element. A first linkage is coupled to the first element, wherein the first linkage drives the first element between a raised position when the strut is in the stowed position and a lowered position when the strut is in the deployed position. The landing gear further includes a second linkage coupled to the trailing arm. The second linkage rotates the trailing arm between a first trailing arm position when the strut is in the stowed position and a second trailing arm position when the strut is in the deployed position.

The embodiments of the disclosed subject matter in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. A landing gear for a vehicle, comprising:
 a strut configured for reciprocating movement between a stowed position and a deployed position; 
 a shock absorber comprising a first element slidingly disposed within the strut and a second element slidingly coupled to the first element; 
 a trailing arm rotatably coupled to the first element, a first end of the trailing arm having a wheel rotatably mounted thereto; 
 a first linkage coupled to the second element, the first linkage driving the second element between a raised position when the strut is in the stowed position and a lowered position when the strut is in the deployed position; 
 a lever coupled to the first linkage; and 
 a second linkage coupled to the trailing arm and comprising a positioning rod pivotably coupled to the lever, wherein rotation of the lever drives the positioning rod to rotate the trailing arm between a first trailing arm position when the strut is in the stowed position and a second trailing arm position when the strut is in the deployed position. 
 
     
     
       2. The landing gear of  claim 1 , wherein the strut is rotatably coupled about an axis, and a drive rod is pivotably coupled about a point, the point being fixedly positioned relative to the axis. 
     
     
       3. The landing gear of  claim 1 , wherein the first element is a piston, and the second element is a cylinder, the piston being partially disposed within the cylinder. 
     
     
       4. The landing gear of  claim 1 , wherein the first element is a cylinder, and the second element is a piston partially disposed within the cylinder. 
     
     
       5. The landing gear of  claim 1 , wherein the first linkage comprises a first link rotatably coupled at a first end to the strut and rotatably coupled at a second end to a first end of a second link, the second link being coupled at a second end to the first element. 
     
     
       6. The landing gear of  claim 5 , the second link comprising a second link engagement surface that contacts an inner surface of the strut when the strut is in the deployed position, wherein an axial load applied to the shock absorber drives the second link engagement surface toward the inner surface of the strut. 
     
     
       7. The landing gear of  claim 6 , further comprising a drive rod, wherein the lever is fixedly coupled to the first link, and the drive rod has a first end pivotably coupled to the lever, rotation of the drive rod moving the second link engagement surface away from the inner surface of the strut when the strut moves toward the stowed position. 
     
     
       8. The landing gear of  claim 1 , the second linkage further comprising:
 a positioning link rotatably mounted to the strut; and 
 a drop link rotatably mounted at a first end to the positioning link and rotatably mounted at a second end to a second end of the trailing arm. 
 
     
     
       9. The landing gear of  claim 8 , further comprising a strut engagement surface formed on the strut and a positioning link engagement surface formed on the positioning link, wherein the strut engagement surface engages the positioning link engagement surface when the strut is in the deployed position. 
     
     
       10. The landing gear of  claim 9 , wherein a tensile load applied to the drop link when the strut is in the deployed position urges the positioning link engagement surface toward the strut engagement surface. 
     
     
       11. The landing gear of  claim 10 , wherein the tensile load in the drop link is reacted into the strut through contact between the positioning link engagement surface and the strut engagement surface. 
     
     
       12. The landing gear of  claim 11 , wherein the tensile load in the drop link results from a vertical load applied to the wheel. 
     
     
       13. A landing gear for a vehicle, comprising:
 a strut configured for reciprocating movement between a stowed position and a deployed position; 
 a shock absorber comprising a first element slidingly disposed within the strut and a second element slidingly coupled to the first element; 
 a trailing arm rotatably coupled to the first element, a first end of the trailing arm having a wheel rotatably mounted thereto; 
 a first linkage coupled to the second element, the first linkage driving the second element between a raised position when the strut is in the stowed position and a lowered position when the strut is in the deployed position; 
 a second linkage coupled to the trailing arm, the second linkage rotating the trailing arm between a first trailing arm position when the strut is in the stowed position and a second trailing arm position when the strut is in the deployed position; and 
 a side brace coupled at one end to the strut, wherein a first end of the second linkage is coupled to the side brace, and a second end of the second linkage is coupled to the trailing arm, movement of the side brace as the landing gear reciprocates between the deployed position and the stowed position rotating the trailing arm. 
 
     
     
       14. The landing gear of  claim 13 , the second linkage comprising:
 a positioning link rotatably mounted to the strut; and 
 a drop link rotatably mounted at a first end to the positioning link and rotatably mounted at a second end to a second end of the trailing arm. 
 
     
     
       15. A landing gear for a vehicle, comprising:
 a strut configured for reciprocating movement between a stowed position and a deployed position; 
 a shock absorber comprising a first element slidingly disposed within the strut and a second element sliding coupled to the first element; 
 a trailing arm rotatably coupled to the first element, a first end of the trailing arm having a wheel rotatably mounted thereto; 
 a first linkage coupled to the second element, the first linkage driving the second element between a raised position when the strut is in the stowed position and a lowered position when the strut is in the deployed position; 
 a second linkage coupled to the trailing arm, the second linkage rotating the trailing arm between a first trailing arm position when the strut is in the stowed position and a second trailing arm position when the strut is in the deployed position; and 
 a rotary actuator operably coupled to the second linkage and configured to rotate the trailing arm as the landing gear reciprocates between the deployed position and the stowed position. 
 
     
     
       16. The landing gear of  claim 15 , the second linkage further comprising:
 a positioning link rotatably mounted to the strut; and 
 a drop link rotatably mounted at a first end to the positioning link and rotatably mounted at a second end to a second end of the trailing arm.